618
FXUS63 KDVN 140844
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
344 AM CDT Fri Jun 14 2024

.KEY MESSAGES...

- Well above normal temperatures next week will bring hot and
  humid conditions to the area. Peak afternoon heat indices
  will be in the 95 to 100 degree range.

- The heat and humidity will come with occasional chances for
  scattered storms from Saturday into late next week. While
  there are chances for rain, prolonged dry periods are
  anticipated as well.

&&

.SHORT TERM /THROUGH SATURDAY/...
Issued at 315 AM CDT Fri Jun 14 2024

Today and Tonight

A ridge aloft will build into the Midwest as surface high
pressure slides across the Upper Mississippi Valley into the
Great Lakes. Expect seasonably warm temperatures today with
highs ranging from the lower 80s across the north to mid/upper
80s central and south. A post-frontal air mass will continue to
advect into the region leading to comfortable humidity with
dewpoints only in the 50s. For the overnight period, ambient
temperatures will drop into the upper 50s to low 60s.

Saturday

A shortwave trough is forecast to eject out of the Southern
Rockies into the central Plains early Saturday with the main
500mb vorticity max staying NW of the local area, traversing
across western Iowa into southern Minnesota. This will keep the
stronger forcing and highest rain chances to the north. Isolated
warm air advection showers and storms are possible on Saturday,
but with most of the area likely to stay dry.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Issued at 315 AM CDT Fri Jun 14 2024

Saturday Night

As the southern periphery of the mid-level shortwave glances
the area late Saturday night, a period of scattered showers and
storms is possible, especially across the northern portion of
the forecast area. NBM rain chances range from near 20% along
I-80 to 30-50% north of Highway 30. Confidence is low on whether
this round of showers and storms impacts portions of the
outlook area, or remains mostly to the north where the stronger
850mb flow and attendant convergence is forecast.

Sunday

Hot and humid conditions are expected with highs in the
low to mid 90s and peak heat indices between 95 to near 100
degrees, highest south of I-80. Subsidence behind the departing
shortwave should result in mainly dry conditions across the
outlook area for the afternoon. A surface low tracking near Lake
Superior will lead to breezy SW winds locally with gusts up to
30 mph, providing some relief from the hot conditions. The
resultant boundary layer mixing could hold dewpoints in the 60s
and prevent much of the area from reaching Heat Advisory
criteria, aside from on an isolated/brief basis.

Next Week

Hot weather is expected Monday and Tuesday with forecast highs
in the low/mid 90s (isolated upper 90s possible on Monday).
Again, dewpoints will be the main player in whether locations
hit Heat Advisory criteria (100 F). The NBM has afternoon
dewpoints in the mid/upper 60s with peak heat indices between 95
to around 100 degrees.

The core of the upper-level heat dome is forecast to set up
over the Eastern U.S. through the middle to end of the week,
placing eastern Iowa and northwest Illinois on the western
fringe. This may allow a surface boundary to drop in from the NW
leading to occasional chances for showers and thunderstorms.
Confidence on any appreciable rainfall is fairly low this far
out. High temperatures are also uncertain for the mid to late
week period. The NBM is a few degrees "cooler", while the EC
deterministic and ensemble mean retrograde the 500mb heat dome
back into the Mid to Upper Mississippi Valley region, leading to
a continuation of the well above normal temperatures and no
reprieve from the heat.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1255 AM CDT Fri Jun 14 2024

VFR will prevail through the period with light winds and mainly
clear skies.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.

&&

$$

SHORT TERM...Uttech
LONG TERM...Uttech
AVIATION...Uttech